strange-steve
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Just received this today, can't wait to get a brew on to give it a spin!
My new toy!
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yeastinfection
Landlord.
keep reading stuff about about ph levels, sounds like a minefield, ive seen pen type readers but they dont seem very accurate,
looking forward to your review of this
looking forward to your review of this
Looks good, I wouldn't know what to do with it though!
strange-steve
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I have one of the cheap yellow pen things, I'll check it against the new one once I get it calibrated.
The reason I got this is that I'm testing out a new philosophy wrt water treatment, one that requires RO water and a pH meter. I'll post about it once I've run a few trials.
strange-steve
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Well I finally got playing with this earlier, not in a brew but just calibration and testing.
The first job was the 2 point calibration using pH 7 and 4 buffers. The little glass contains RO water for rinsing. As you can see it didn't need much adjustment out of the box, it was just a few hundredths high. Then into the 4 for the second calibration point.
I then checked my cheap eBay meter in the pH 7 buffer and as you can see it wasn't too far away. I adjusted it to 7 with the little screw on the back. Then checked it in the 4 and it was spot on.
I then checked them both in some starsan to see how they compared and they were surprisingly close. Then tested in some Sierra Nevada Pale Ale and again spot on.
So the cheap meter, with only a single point calibration at pH 7 was accurate down to pH 2.2 which is pretty impressive.
The first job was the 2 point calibration using pH 7 and 4 buffers. The little glass contains RO water for rinsing. As you can see it didn't need much adjustment out of the box, it was just a few hundredths high. Then into the 4 for the second calibration point.
I then checked my cheap eBay meter in the pH 7 buffer and as you can see it wasn't too far away. I adjusted it to 7 with the little screw on the back. Then checked it in the 4 and it was spot on.
I then checked them both in some starsan to see how they compared and they were surprisingly close. Then tested in some Sierra Nevada Pale Ale and again spot on.
So the cheap meter, with only a single point calibration at pH 7 was accurate down to pH 2.2 which is pretty impressive.
gedburg101
Well-Known Member
Would you recommend one of the cheaper ones then?
I've never really got into the water chemistry side but I'm sure it's something I need to address.
I've never really got into the water chemistry side but I'm sure it's something I need to address.
strange-steve
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I'll be using the two meters side by side for my next brew which will be more telling.
From what I understand, the problem with the cheap meters isn't that they aren't accurate but rather that they don't hold their calibration, but it's quick and easy to calibrate so that may not really be an issue.JapanBrew said:
strange-steve
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Many thanks to photobucket for screwing up another of my threads due to lost pictures 
Anyway, this is the one showing the comparison between the two meters:
Well in preparation for tomorrow's brew day I checked both meters again in the buffers and 3 weeks after calibration they are both still bang on, even the cheap one! Maybe those pen type meters aren't as bad as everyone says :hmm:
I'll be using them both tomorrow throughout the brew so I'll report back.
Anyway, this is the one showing the comparison between the two meters:
Well in preparation for tomorrow's brew day I checked both meters again in the buffers and 3 weeks after calibration they are both still bang on, even the cheap one! Maybe those pen type meters aren't as bad as everyone says :hmm:
I'll be using them both tomorrow throughout the brew so I'll report back.
private4587
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I have one of those cheap yellow meters, are you supposed to use both the sachets during the calibration process i.e 6.8 and 4.2
strange-steve
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A more expensive meter will have two adjustment screws on it, one for offset (calibrated at around pH 7) and one for slope (calibrated at around pH 4) that's why you do a 2 point calibration. If your pH pen is like mine it'll only have one adjustment screw which is for offset, so you can't calibrate the slope. However you should still do the two point calibration, it just means that it's possible that you won't be able to calibrate to exactly 7 and 4 (or 6.8 and 4.2 in your case), but if that happens you can just split the difference and it should be fairly close.
strange-steve
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This is my first time using this for a brew and I'm pleased with how it went. I used the pen meter as well for another comparison and again the results were very close. The bottom pics were measured about 10 mins after dough in and the top ones were about 30 mins into the mash.
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